First of all according to your post Title it's shown that, still you have confusion about Bitcoin future. but you have taken a big decision and done a risky work. there is no doubt about bright future of Bitcoin but anything can happen with crypto currency. if it's price go down, it will recover must after certain time. so that you have to hold your coin to recover price when the price go down. so i think this is the best time buy BTC by your unnecessary money. as a result if you need hold your coin for the long time to get big profit, you can not face any financial problem in your real life. wish you good luck

my point is, "Buy BTC by unnecessary Money not by Land/House sell's money"